Cylindrical grinding machine



Dec. 28, 1937. H. E. BALslGER CYLINDRICAL GRINDING MACHINE Filed March 25, 1951 2 sheets-smet 1 lNvr-:NToR

Haro/d EBU/Ji en BY d /f l A ORNEY Dems. 28, 1937. I H. z-z. BALslGER CYLINDRICAL GRINDING MACHINE Filed March 23 1931 2 Sheets-Sheet 2 INVENTOR A ORNEY Patented Doc. 28, 1937 CYLINDRICAL GRINDING l Harrold E. Balsiger, Waynesboro, Pa., assigner to i Landis Tool Company, Waynesboro. Pa., a' cor- H poration of `Pennsylvania Application March 23,

9 Claims.

Ihis invention relates to machines i'or grinding-plain cylindrical surfaces and particularly to a carriage traverse mechanism.

An object of the invention is to provide means for controlling movement of the work carriage to insure smooth operation 'at all speeds.

yA' further object is` to provide means for maintaining a constant supply of iluid inthe control means. 1 f

A still further object is to provide/means operated by movement oi thel work carriage for operating the wheel feed. A Y

`Further objects and advantages will become apparent as thedescription proceeds.

Referring. to the accompanying drawings, which are made a part hereof p and on which similar reference characters indicate similar parts I 4 K y Figure 1 is a frontelevation of the machine. Figure 2, a front view of the automatic wheel feed mechanism on an enlarged scale, and i yFigure 3, a diagrammatic sketch'of the draulic mechanical and electrical lay-outs.

`In the drawings reference character I0 indicates the base of agr'inding machine having a work carriage mounted thereon land having a wheel baser I2 movable'toward and'from the work carriage in a well knownmanner. The wheel base carries a grinding wheel I3 which is driven by means of an electric motor I4 through a belt I5.V The work carriage has a tail stock I6 mounted at one end and a head stock I'I at the other, the headstock being driven, by means of an electric motor I8.- The wheelbase carrying the grinding wheel is fed into the work by mechanism vshown `in detail in Figure 2. This consists of a ratchet wheel I9 mounted on a shaft which shaft is connected to any well-known gearing mechanism for moving the 4()y Wheel base forward. An arm 2| on the shaft 20 has a Apawl 22 at its outer end engageable with the teeth on the ratchet wheel I9. Se-

cured'to or made integral with the arm 2| is an arm 23 having a gear segment cut thereon with 46 rock arm 25. The other end of the rock arm engages a spool on the outer endofV a piston rod 26. The piston rod carriesa piston 2'I'operable in a cylinder 28. Fluid lines 29 and 30 connect `the cylinder at opposite sides/.oi the piston. Pressure iluid from aline 3| is'delivered to lines 29 and 30 througha valve 32./ The valve consists of a pair of disks against theupper of which is positioned a compression spring 33. Valve 55 which engages gear teeth 24 on one end of a stem34 hasa yspool 35thereon engaged by one l 1931, serial No. 524,711@Y end oi' a lever 36. `'I'he other end oi this lever carries a'ro'ller 31 VVKwhich is engaged by a cam 38 attached to the work carriage II. The work i carriage may be provided with a dcgateach end so as to operate vthe valve at each end of the 5 stroke or if desired 'only a'single cam may be provided-.on the work carriage so that thevalve will be .operated only at oneend of the travel of `the work carriage. Pressureiiuid is supplied toV the line 3| by apump 39. "i 10 The work carriage is operated by means of hydraulic motors comprising cylinders 40 and" having pistons 80 and 42 movable therein. Piston rods 43 and 44 -are each attached at their outer ends .to ,the work carriage II. The cylin- 15 der s 40 and 4| are connected at-the sides opposite the piston rods of each by means oi a iiuid` line 45 in which line is positioned a control valve 46. Fluid line 3| is connected with the line 45 at each side of the valve 46 and is provided 20 with means such aslcheck'valves 41 for checking backxow from lline 45. The purpose 01" this construction is to maintain the lines 45 constantly lled with pressure iluid so as* to insure smooth operation atall times.

the work carriage is varied by the `adjustable throttle valve 46 since fluid must flow from one side of one piston tothe opposite side of the other during movement of the work carriage. The pistons 80 and 42 are operated by fluid sup- 30 plied to them by fluid lines 48 and 49. Pressure is supplied to the lines 48 and49 from line 50 from the pump through ports 5|' and 52. A valve 53 controls passage of4 iluid from'the portV 5| to the 'port 52 and a reversing valve 55 con- 35 trols passage of iluid fromport 52 to either oi" the lines 48 or ,49. 4Pressure uid from the motors is exhausted through lines 56 and 51 to a reservoir not shown in the base of the machine. Reversing valve 55 is operated lthrough a valve 40 stem 58 attached to the lower end of a reversing valve shifting mechanism. .'I'he reversing lever 59 is operated by dogs 60 ron the work carriage. The lever 59 has a roller 6I on its lower end which engages cam surfaces onithe top `of a 45 plunger 62 for throwing the reversing lever and holdingit in the thrown position in amanner y well-known in machines ofthis type. The carriage II maybe manually traversed by hand wheel Il' acting through any of the well known .50 traverse mechanisms. p f A spring pressed relieffvalve 63 maybe posi-rv tioned between pressure line and exhaust line 51. The valve 53 is connected `byemeansof a valve stem 64 withone y'end of an arm 65 to the 55 l-fFlcr.v

The speedl of 25 other end of which is attached a valve stem 66 for operating a valve 61 which controls ports 68 and 83. When positioned to place port 8l in communication with port 69, i. e. when valve 61 is moved to the right the work carriage may be freely manually moved since fluid may freely flow from cylinder 4| without passing through throttle valve 46. For hand traverse the pressure fluid in the piston rod end of the cylinders may pass from the reversing valve through ports 52 and 18 to passage 56, from it may pass to either of the passages 48 or 49, depending on the position of the reversing valve 55. Valves 53 and 61 are operated by means of a lever 10 which has a link 1| attached to its lower end, the link being attachedat its other end to the arm 65. The lever 10 has on its lower end a cam 12 which engages a roller 13, on a limit 1 switch 14. 'I'his switch controls circuit through lines 15 tothe work drive motor I8. Air bleed pipes 19 are connected to each end of cylinders 40 and 4|. l

In operation the lever 10 is moved to the position shown in Figure 3. Fluid from the pump 39 is delivered through line 50, port 5|, port 52 and line 48 to the left of piston 80. This will move the work carriage to the right. Thespeed of travel, however, of the carriage will be controlled by the speed with which fluid from the cylinder 40 will flow through line 45 and needle valve 46 to the left of piston 42 in cylinder 4|. When the carriage has reached its limit of travel to the right a dog on the left end of the carriage will engage reversing lever 59 and swing it'to the right. This will shift reversing valve 55 so as to close line 48 andplace line 49 in communication with port 52. Line 48 in the meantime may exhaust through line `56. Pressure fluid therefore passes through line 49 to the right of piston 42 to move the carriage to the left. This operation continues indefinitely with the carriage traversing back and forth past the grinding wheel. Pressure fluid from the pump 39 likewise passes through line 58, line 3| and through valve 32 to cylinder 28. When the valve 32 is in the position shown in Figure 3 pressure fluid from line 3| may pass through the line 30 to the left of piston 21. This moves piston 21 to the right and rocks the rock arm 25 counterclockwise to rotate the arm 2| clockwise to move the ratchet wheel I9 to move the grinding wheel base toward the work. As soon as the cam 38 releases the roller 31 spring 33 moves the valve 32 to close line 30 and to place line 29 in communication with line 3|. Fluid then passes from pressure line 29 to the right of the piston 21 and this swings the arm 2| and the pawl 22 counterclockwise to place them in position for the next operation. When the valve 32 moves downwardly of course pressure fluid line 30 is placed in communication with' exhaust line 16 and when the valve is moved in the position in which it is shown in Figure 3 line 29 is open to the exhaust. An adjusting nut 11 may be provided on the piston rod 26 to control the extent of movement of the piston rod to control the distance through which the grinding wheel. is fed into the work,

It will be obvious to those skilled in the art that various changes may be made in my device without departing from the spirit of the invention and therefore I do not limit myself to what is shown in the drawings and described in the specification, but only as indicated by the appended claims.

Having thus fully described my said invention, what I claim as new and desire tosecure by Letters'Patent, is:

l. In a machine having a carriage, a hydraulic h I I emotor for traversing said carriage comprising two cylinders, a piston in each cylinder, means connecting said motor with the said carriage, means for supplying fluid under pressure to one end of each cylinder, a closed conduit connecting the opposite ends of said cylinders with each other to permit the fluid from one cylinder to pass to the other, means for restricting the flow of fluid through said conduit, and automatic means toreplace leakage from said cylinders and said conduit.

2. In a machine having a carriage, a hydraulic motor for traversing said carriage comprising two cylinders, a piston in 'each cylinder, means for supplying operating fluid to one end of each cylinder, a closed conduit connecting the opposite ends of said cylinders with each other to permit the fluid from one cylinder to pass to the other, and adjustable means for restricting the flow of fluid thru said conduit.

3. In a machine having a carriage, a dual piston four chamber hydraulic motor for traversing said carriage, means for supplying operating fluid to two of said chambers, a closed conduit connecting the other chambers with each other to permit the fluid topass from one chamber to the other, and adjustable means for restricting the flow of fluid thru said conduit.

4. In a machine having a carriage, a dual piston four chamber hydraulic motor for traversing said carriage, means for supplying operating uid to two of said chambers, a closed conduit connecting the other chambers with each other to permit the fluid to pass from one chamber to the other, means for restricting the flow of fluid through said conduit, and means to bypass said restriction.

5. In a machine-having a carriage, a dual piston four chamber hydraulic motor for traversing said carriage, means for supplying operating fluid to two of said chambers, a closed conduit connecting the other chambers with each other to permit the fluid to pass from one chamber to the other, means for restricting the ow of fluid through said conduit, and means for cutting ci! the supply of fluid to said cylinders and for bypassing fluid around said restricting means.

6. In a machine having a carriage, a hydraulic motor for traversing said carriage comprising two cylinders, a piston in each cylinder, piston rods connecting said pistons with said carriage, means for supplying operating fluid to one end of each cylinder, a lclosed conduit connecting the opposite ends of said cylinders with each other to permit the fluid from one cylinder to pass to the other,

whereby said fluid opposes each of said pistons' alternately to control movement of said carriage in both directions.

7. In a machine having a carriage, a dual piston four chamber, hydraulic motor for traversing said carriage, means for supplying operating fluid to two of said chambers, a closed circuit-connecting the other chambers with each other to permit fluid to pass from one chamber to the other, automatic means for replacing leakage in said conduit and the chambers connected thereto, means for restricting the flow of fluid through said conduit and means for cutting off the supply of fluid to said cylinders and for bypassing the fluid around said restricting means.

8. In a grinding machine, a carriage, manual means for effecting a traversing movement of said carriage, power means for effecting a traversing movement of said carriage comprising a hydraulic motor having four chambers, a source comprising a bypass around said adjustable valve whereby to provide an unobstructed manual traverse. v

9. In a grinding machine, a movable carriage, manual means for eiecting a traversing movement of said carriage, power means for eficting a traversing movement of said carriage comprising a uid motor, a supply-of uid'under pressure, a start and stop lever for controlling said supply and valve means operated by said lever upon shifting same to a stop position for connecting said fluid supply with an exhaust line while maintaining a connection between'saidl supply and said motor, said valve means when in stopI position providing an unobstructed passage be'` tween opposite sides of said motor to permit the manual traverse of said carriage. g

HAROLD E. BAISIGER. 

